The present invention relates to a control system, a relay device and a control method and relates to, for example, a technique of performing control by transmitting and receiving data between a plurality of devices.
In recent years, in a social background which demands reduction of traffic accidents, reliving and easing of traffic jam and improvement of comfort of drivers, a drive assist network system for automatic driving is rapidly spreading. Statistical data shows that a cycle to buy a new car is a very long cycle such as about 10 years or more. By contrast with this, since each automaker makes a great effort to reduce traffic accidents, a new drive assist application program is developed at a shorter cycle than a cycle to buy a new car, and is applied to the latest car at the time of the development.
In the drive assist network system (in-vehicle system), each domain (a block in in-vehicle units) or each ECU (Electronic Control Unit) cooperates with each other. In this regard, a development span of an actuator control domain and ECU is generally very long such as 5-year units or 10-year units. Meanwhile, a development span of a drive assist domain and ECU is in a year unit. Hence, to enable addition of a new drive assist ECU for a purpose of updating a function of the drive assist network system, mounting in advance a mechanism which assumes the addition of a new drive assist system is necessary yet is very difficult.
Japanese Unexamined Patent Application Publication No. 2002-314558 discloses a technique of solving such a problem. A communication system disclosed in Japanese Unexamined Patent Application Publication No. 2002-314558 enables addition of an ECU by mounting on each ECU in advance a mechanism which changes items of individual data whose transmission destinations are only specific ECUs to items of global data whose transmission destinations are all ECUs according to a global change request.